How do earthquakes cause tsunamis?
Tsunamis are caused when an earthquake causes the seafloor to rise of fall. This is when two tectonics plates collide into each other at a plate boundary. The denser plate would subduct under the other plate, which leads to a rise or fall of the seafloor. This movement of the seafloor will cause a rapid displacement of water, and a wave would form. As the wave approaches the coastline, it would get higher as the seafloor gets shallower, causing a tsunami. The shockwaves produced by the earthquake would radiate out and cause waves to form too.
